1. Field of the Invention
The present invention relates to a technique of mounting a semiconductor light-emitting element such as a light-emitting diode and a plane-emitting laser that can be used in, for example, a semiconductor device, an illumination device, a display device, and the like.
2. Description of the Related Art
In recent years, due to the advancement of semiconductor technology, a light-emitting diode and a plane-emitting diode that emit light in a blue to ultraviolet short-wavelength range have been realized. By using them, white light sources utilizing the excitation of phosphors are being developed extensively. For example, white light can be obtained by coating a blue light-emitting diode with a phosphor that emits light in yellow. Because of this, white light sources are being put into practical use for various kinds of displays and illumination. Furthermore, the following attempt also has been made: an ultraviolet light-emitting diode with a wavelength of 300 to 400 nm is used as a light source, and phosphors of three primary colors of red, green, and blue are excited by the diode, whereby more natural white color is obtained.
Various methods have been proposed for mounting the above-mentioned type of a light-emitting device composed of a light-emitting diode and a phosphor, (e.g., JP 11(1999)-298048 A, JP 2002-76444 A, etc.). Hereinafter, the configuration of a conventional white light-emitting device including the above-mentioned combination of a light-emitting diode and phosphor will be described with reference to FIG. 8.
FIG. 8 is a cross-sectional view showing an exemplary configuration of the conventional white light-emitting device. A blue light-emitting diode 2 is mounted with a silver paste 3 on a support substrate 1 on which an electrode pattern 22 is formed via an insulating film 21. Terminal electrodes 4 are formed on a surface of the light-emitting diode 2, and the terminal electrodes 4 are electrically connected to the electrode pattern 22 on the support substrate 1 with gold wires 23. Furthermore, a sealant 24 containing a phosphor is formed so as to cover the light-emitting diode 2.
When electric power is supplied to the light-emitting diode 2 through the electrode pattern 22, the light-emitting diode 2 emits light in blue. A part of the light is absorbed by the phosphor in the sealant 24, whereby the phosphor emits light in yellow. The yellow light emitted from the phosphor is mixed with a part of the blue light transmitted through the sealant 24 to obtain a white light source.
However, the above-mentioned configuration has the following problems. With this configuration, wire bonding is required for forming the gold wires 23. Furthermore, during wire bonding, an excess stress may be applied to the light-emitting diode 2 and degrade it. Furthermore, with the conventional configuration, it is required that the sealant 24 is formed after wire bonding, which increases a production cost.
Furthermore, due to the stress generated when the sealant 24 is cured, the gold wires 23 may be disconnected from the terminal electrodes 4 or the electrode pattern 22. These problems lead to main factors for decreasing a yield in a light-emitting device, particularly in which a number of light-emitting diodes are arranged in an array. Furthermore, with the conventional configuration, it is difficult to decrease the thickness of a device due to the presence of the gold wires 23.